Work study is the systematic examination of the methods of carrying on activities so as to improve the effective use of resources and to set up standards of performance for the activities being carried out.

Work study then aims at examining the way an activity is being carried out, simplifying or modifying the method of operation to reduce unnecessary or excess work, or the wasteful use of resources, and setting up a time standard for performing that activity. The relation between productivity and work study is thus obvious.

If work study results in cutting down the time of performing a certain activity by 20 per cent, merely as a result of rearranging the sequence or simplifying the method of operation and without additional expenditure, then productivity will go up by a corresponding value, that is by 20 per cent. To appreciate how work study acts to cut down costs and reduce the time of a certain activity, it is necessary to examine more closely what that time consists of.

How the Total time of a Job is Made Up

The time taken by a worker or a machine to carry out an operation or to produce a given quantity of a certain product may be considered as made up in the following manner:

Work content means, of course, the amount of work "contained in" a given product or a process measured in "work-hours" or "machine hours".

- A work-hour is the labor of one person for one hour.
- A machine-hour is the running of a machine or piece of plant for one hour.

The basic work content is the time taken to manufacture the product or to perform the operation if the design or specification of the product or service provided were perfect, if the process or method of operation were perfectly carried out, and if there were no loss of working time from any cause whatsoever during the period of the operation (other than legitimate rest pauses permitted to the operative).

The basic work content is the irreducible minimum time theoretically required to produce one unit of output.This is obviously a perfect condition which never occurs in practice, although it may sometimes be approached, especially in line manufacturing or process industries. In general, however, actual operation times are far in excess of it on account of excess work content.

The work content is increased by the following:

A. Work content added by poor design or specification of product or its parts, or improper utilization of materials

Poor design and frequent design changes
The product may be designed in such a way that it may require a large number of non-standard parts causing a lengthy time of assembly. Excessive variety of products and lack of standardization of products or their parts may mean that work has to be produced in small batches, with time lost as the operator adjusts and shifts from one batch to the next.

Waste of materials
The components of a product may be so designed that an excessive amount of material has to be removed to bring them to their final shape. This increases the work content of the job and wastes material as well. Operations requiring cutting in particular need careful examination to see if the resulting waste can be reduced to a minimum or reused.

Incorrect quality standards
Quality standards that are too high or too low can increase work content. In engineering industries, insisting on sometimes unnecessarily tight tolerances requires extra machining and a corresponding waste of material. On the other hand, setting tolerances too loose may result in a large number of rejects. Deciding on the appropriate quality standard and tire method of quality control is an important efficiency consideration.

B. Work content added by inefficient methods of manufacture or operation

Poor layout and utilization of space
The space used for any operation represents an investment. Proper utilization of space is an important source of cost reduction, particularly when an enterprise is expanding and needs an increased working area. Furthermore, a proper layout reduces wasted movement, time and effort.

Inadequate materials handling
Raw materials, parts and finished products are invariably being moved from one place to another throughout a production operation. The use of the most appropriate handling equipment for the purpose can save time and effort.

Ineffective method of work
A sequence of operations may be well planned but each or some of them done in a cumbersome manner. By examining the way a certain operation is carried out and devising a better method, ineffective time can be reduced.

Poor planning of inventory
In every operation, raw material is usually ordered and stocked ahead of time and at every stage of the operation an inventory of so-called "materials-in-progress" or semi-finished products and various parts are temporarily stocked waiting to be processed. These various inventories represent a tied-up investment. A proper inventory control system when installed can minimize such an idle investment while ensuring that the operators do not run out of the material needed.

Frequent breakdown of machines and equipment
Poor maintenance results in machinery and equipment that are often out of action, and idle time ensues while waiting for repairs. Installing a preventive maintenance system and mounting maintenance campaigns would ensure the smooth functioning of machinery and equipment.

C. Work content resulting mainly from the contribution of human resources

Absenteeism and lateness
If management fails to provide a safe and satisfying work climate, workers could respond by absenteeism, lateness or deliberately working slowly.

Poor workmanship
If workers are improperly trained, the resulting poor workmanship can mean that the job has to be done again. Losses may also occur because of wasted material.

Accidents and occupational hazards
If management fails to provide a safe and healthy place to work, accidents
or occupational illnesses can occur, with resulting effects on morale and increased absenteeism.

Source:

C.R.Wynne- Roberts and George Kanawaty, Introduction to Work Study, International Labour Office. You can obtain this fine book
here